How to process Queued WCF Web service requests

I have a requirement to Queue web service requests and then process each request based on priority and request time. And then send response back.

The approach I'm thinking is as follows 1 Create a web service method to submit requests and enqueue requests.

2 Create two queues (high priority requests and lower priority requests)

3 Create a Processing method to process each request one at a time(dequeue the high priority queues first if it exists) process and then store the response

4 Create a dictionary to store response for the respective request. 5 create a web service method to get the response

I'm thinking to use in memory queue since I expect few number of requests queued at a time.

The problem I'm having is in step 3. I want the processor method to continuously run as long as there are requests in the queue.

How can I accomplish step 3 using WCF web service ? I'm using .NET 4.0 environment. I really appreciate any ideas or suggestions.

Thanks

I would create my service contract to make it clear that the operations will be queued. Something like:

[OperationContract]
string EnqueueRequest(int priority, RequestDetails details);

[OperationContract]
bool IsRequestComplete(string requestId);

I would have EnqueueRequest place each request into an MSMQ queue. I'd have a Windows Service processing the requests in the queue. That service would be the only process that has access to the SDLC device.

Have you coded the service in a plane jane, meat and potatoes way and profiled to see if it's necessary to queue requests? There is overhead involved in queuing. It's a good idea to do some measurement and see if just servicing requests is adequate.

Another way to approach it would be to use Microsoft Message Queue. Here is even some tight integration between message queues and WCF. The thought is, if you do actually need a queue, why not use something that is already built and tested.